I am curious - what is your workflow with Route VI? Do you use instrument during the game? Anyway I am not even close to lvl 90 but have the same problem. But I think we can at least partially blame busy mixes. There is just so much going on - not just piano and bass playing root notes :)

I think that it is really normal to have a big gap between tonegym exercises, because with pop song you have to take into account all of the other sensory imput that you get, so it might make it harder, you will get there eventually !

Im nowhere near 90 on route VI but I have the same experience where I want to hear chord progressions in the actual songs I listen to but cant. I don't think route VI is very useful to this end or would ever get you there. Ive seen a lot of people on here recommend chord crush. I tried it and liked it but havent gotten the payed version yet.

I don't use an instrument for Route VI. I got used to the feeling of chord functions. So similar feelings like the iii and the vi in a major key are more difficult, but since I can repeat the chord progression many times I can focus on the exact feeling.
That being said, a lot of winning in Route VI is based on having a multiple choice question. So I just eliminate answers that cannot be right, naming the chords without answers would be way harder.
But in real songs I don't feel any chord function. I can tell when there is a chord change most of time, but the feeling is so impure, I can't even tell if I'm listening to a major or minor chord.

I am level 136 and if I have a plain progression with I-V-IV and some other simpler chords I can sort of figure it out. However if it is arpeggiated or spread out I really struggle. I have separately worked on figuring out key signature, I do it by figuring out the melody first. Route iv (and it pains me to say this because of the time I have spent on it) could be a lot more useful. at level 136 I am really having trouble because of these progressions they are the best ones for training I have ever gotten but I just cannot figure them out. This is because they are i ii iii and vi chords that are in the same places. level 135 had similar things and the only way I passed it was by the lifesaver.
Ed di nailed it! The multiple choice is what makes it possible to travel so far without many results.

The reason this is so hard is you cannot listen to Major/minor, they are in all inversions, and there was little focus on this sort of progression previously.(it removes the multiple choice)